Positives:
– They liked the small size and light weight of the lens.
– The Tamron is nearly as sharp as the more than two times more expensive Sony 24-70mm GM lens.
– The Tamron also comes surprisingly close to the Zeiss Otus quality!
– CA is not an issue
– Autofocus seems like to work as well as Sony native lenses
Negatives:
– Missing focus button on the lens.
– Missing MF-AF switch
– 28mm at the wide end and not 24mm
Conclusion? Dream lens for a very good price!
https://www.sonyalpharumors.com/first-review-of-the-new-tamron-28-75mm-f-2-8-fe-lens-dream-lens-for-a-very-low-price/ 
First review of the new Tamron 28-75 f2.8 FE
– They liked the small size and light weight of the lens.
– The Tamron is nearly as sharp as the more than two times more expensive Sony 24-70mm GM lens.
– The Tamron also comes surprisingly close to the Zeiss Otus quality!
– CA is not an issue
– Autofocus seems like to work as well as Sony native lenses
Negatives:
– Missing focus button on the lens.
– Missing MF-AF switch
– 28mm at the wide end and not 24mm
Conclusion? Dream lens for a very good price!
https://www.sonyalpharumors.com/first-review-of-the-new-tamron-28-75mm-f-2-8-fe-lens-dream-lens-for-a-very-low-price/